Structured beams at THz frequencies for sensing and wireless communications

Abstract

We report recent advances in using structured terahertz (THz) electromagnetic beams for wireless communications and radar sensing. First, we show that many practical THz links will operate in the transmitter near field, where optics-inspired beam shaping can provide new capabilities. In particular, we study Airy-like and caustic beams that follow curved trajectories, thus offering improved resilience to blockage, interference mitigation, and enhanced physical-layer security. Second, we present results from a scaled THz radar testbed used to emulate complex low-frequency radar scenarios in a compact laboratory setup. Experiments with orbital angular momentum (OAM) beams reveal target-dependent scattering signatures. Using a simple Laguerre-Gaussian phase model, we demonstrate that these signatures can be exploited to increase backscattered power.